Relationship Between Serum High-Sensitivity C-Reactive Protein and Myocardial Infarction in a General Japanese Population

Background Due to ethic differences in its serum levels, clinical applicability of high-sensitivity C-reactive protein (hsCRP) to the primary prevention of atherosclerotic events has not completely been established in Japanese people whose hsCRP levels are lower than in Western people. This study investigated the relationship between hsCRP and myocardial infarction (MI) in general Japanese people. Methods In relation to hsCRP, the incidence of MI was determined in a multiregional population-based prospective cohort study (n = 6,637; mean age 54.9 years; 2,513 men/4,124 women). Results Fifty-six cases of MI were confirmed during a follow-up period of 10.7 years. The cut-off levels of hsCRP between the highest quartile (fourth quartile) and the other quartiles combined were 0.368 mg/l in men and 0.279 mg/l in women. The hazard ratio (HR) of the highest quartile for MI was significantly greater than that of the other quartiles combined (multivariate-adjusted HR: 2.07, 95% confidence interval: 1.03–4.15) in men, but not in women (1.03, 0.35–2.21). Conclusions In this population, serum hsCRP measurement predicted MI in men, but not in women. Under the low hsCRP level, a method of applicability of hsCRP to a risk assessment for preventing MI among Japanese people should be further explored.